The present invention relates to a dial and pointer assembly for displaying a measurement of a property, characteristic or condition, for example, a speedometer for indicating the speed of a vehicle.
The use of a dial-type display for indicating a measured property, characteristic or condition is common among many of today""s industries. For example, a dial and pointer display is frequently used in a vehicle as a speedometer. FIG. 1 depicts a typical vehicle speedometer 2, which includes a dial 4 and a pointer 6. Dial 4 is marked with gradations corresponding to an increasing value of a property, such as a vehicle""s speed in miles per hour. In response to a measurement of the vehicle""s speed, pointer 6 rotates either clockwise or counterclockwise so that the tip of pointer 6 points to the appropriate value on the dial that corresponds to the measured speed of the vehicle.
Typical pointer and dial displays are not inherently illuminated. They require a separate light source to illuminate the display, thereby making it visible in dark environments, such as at night. One common way to illuminate a pointer is to locate a light source inside of a translucent pointer, thereby making the pointer glow. However, this method simply illuminates the pointer, not the dial. To illuminate the dial, it is known to mount one or more fixed light sources either around the dial, thereby illuminating the entire dial directly, or alternatively, behind the dial in order to illuminate the entire dial through backlight.
The present invention relates to an illuminated dial display comprising a dial and a pointer. One or more light sources, which is/are separate and external from the pointer, illuminates the pointer itself and a region of the dial around the pointer, leaving the remaining portion of the dial dark.